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1.
Campylobacter jejuni is the most important cause of bacterial gastroenteritis in humans. It is a commensal in many wild and domestic animals, including dogs. Whereas genotypes of human and chicken C. jejuni isolates have been described in some detail, only little information on canine C. jejuni genotypes is available. To gain more information on genotypes of canine C. jejuni and their zoonotic potential, isolates from routine diagnostics of diarrheic dogs as well as isolates of a prevalence study in non-diarrheic dogs were analyzed. Prevalence of thermophilic Campylobacter among non-diarrheic dogs was 6.3% for C. jejuni, 5.9% for Campylobacter upsaliensis and 0.7% for Campylobacter coli. The C. jejuni isolates were genotyped by multi locus sequence typing (MLST) and flaB typing. Resistance to macrolides and quinolones was genetically determined in parallel. Within the 134 genotyped C. jejuni isolates 57 different sequence types (ST) were found. Five STs were previously unrecognized. The most common STs were ST-48 (11.2%), ST-45 (10.5%) and ST-21 (6.0%). Whereas no macrolide resistance was found, 28 isolates (20.9%) were resistant to quinolones. ST-45 was significantly more prevalent in diarrheic than in non-diarrheic dogs. Within the common time frame of isolation 94% of the canine isolates had a ST that was also found in human clinical isolates. In conclusion, prevalence of C. jejuni in Swiss dogs is low but there is a large genetic overlap between dog and human isolates. Given the close contact between human and dogs, the latter should not be ignored as a potential source of human campylobacteriosis.  相似文献   

2.
This study was aimed at determining the genetic diversity of Campylobacter jejuni from healthy ruminants and poultry, and study by multilocus sequence typing (MLST) their links to human isolates in Spain. MLST analysis of 160 animal isolates generated 45 sequence types (STs, nine of them new to this study), that clustered into 18 clonal complexes (CC) and nine singletons. The 71 isolates from humans generated 28 STs (13 CC plus four singletons). Only 11 STs and nine CCs were shared by humans and animals (particularly from dairy cattle and sheep), mainly corresponding to sporadic cases rather than outbreaks, probably as an adaptation of the general human population to the types commonly circulating in livestock. PCR analysis of the distribution of four virulence-associated genes detected the cdtABC gene cluster in all 160 isolates but with a 700-bp deletion in four of them, and amplified the virB11, cgtB and wlaN genes in 4.7%, 21.3% and 21.9% respectively. A subset of 87 C. jejuni animal isolates analysed using flaA PCR-RFLP, MLST and pulsed-field gel electrophoresis generated 31, 38 and 55 types respectively. The combined typing approach used provided reliable inter-strain relationships, confirming the co-existence of several strains in some farms, but also identifying identical genotypes sampled over a wide temporal span in different environments and hosts. Typing results confirmed a high genetic diversity of C. jejuni in our region and suggested that ruminants are also important sources for human infection. MLST data provided will help to obtain a more comprehensive image of the population structure of C. jejuni and establish reliable source attribution schemes.  相似文献   

3.
Campylobacter jejuni isolates from a national Swedish Campylobacter monitoring in broilers were characterized by multilocus sequencing typing (MLST) in order to study the genetic diversity of this bacterial population. Isolates were initially characterized by pulsed-field gel electrophoresis (PFGE). One hundred were chosen for MLST genotyping. PFGE identified 69 distinct types compared to 44 different sequence types (STs) identified with MLST. Eighteen STs had not been described previously, while the remaining 26 STs were assigned to previously known clonal complexes. The majority of isolates were of genotypes noted in broilers and in humans in earlier studies. However, three clonal complexes, ST-206 complex, ST-677 complex and ST-1034 complex, previously associated with wild bird and environmental samples, were among the genotypes found. This study shows that most of the Swedish broiler isolates were of genotypes noted as common in broilers. However, it also highlights the potential influence of environmental sources on the broiler C. jejuni genotypes.  相似文献   

4.
Campylobacter in the dog: a clinical and experimental study   总被引:3,自引:0,他引:3  
Faecal samples from 54 dogs with diarrhoea and 54 control dogs were cultured for Campylobacter, Salmonella and Yersinia species and controlled for enteric viruses. The campylobacter were identified as either C jejuni/coli or C upsaliensis. In the diarrhoeic group 16 dogs (29.6 per cent) were positive for campylobacter, 10 C upsaliensis and six C jejuni/coli. Concomitant infection with parvovirus was evident in six of the dogs with diarrhoea and campylobacter-positive faecal cultures. In the control group 13 dogs (24.1 per cent) were positive for campylobacter; three of the isolates were C upsaliensis and six C jejuni/coli. Four isolates could not be identified. The most prominent clinical findings in naturally occurring cases were an acute onset of vomiting (12 of 16), diarrhoea (16 of 16) which was often haemorrhagic (nine of 16) and a raised rectal temperature. Dogs were infected experimentally with both C jejuni (three dogs) and C upsaliensis (three dogs). The challenge strains could be identified in faecal samples from all the dogs, but clinical signs of diarrhoea were seen in only one dog infected with C jejuni. Soft faeces was passed by one dog infected with C upsaliensis. It is concluded that C jejuni/coli or C upsaliensis are either primary pathogens or, after predisposing factors such as virus infections, act as secondary pathogens. It also seems probable that Campylobacter species are present in the intestinal flora of the normal dog.  相似文献   

5.
Campylobacter spp. are the most common cause of bacterial gastroenteritis worldwide and have been isolated from a wide number of different hosts and environmental sources. Waterfowl is considered a natural reservoir for this zoonotic bacterium and may act as a potential infection source for human campylobacteriosis. In this study, faecal samples from 924 barnacle geese were tested for the presence of C. jejuni and C. coli. The resulting C. jejuni and C. coli populations were characterized by multilocus sequence typing (MLST), structure analysis by BAPS and phylogenetic analysis based on full genome sequences. The prevalences of C. jejuni in barnacle geese faeces were 11.5% and 23.1% in 2011 and 2012, respectively, and only 0.2% of the samples were positive for C. coli in both years. Furthermore, a possible adaption of the clonal complexes (CCs) ST‐702 and ST‐1034 to the barnacle geese reservoir was found, as these two CCs represented the majority of the typed isolates and were repeatedly isolated from different flocks at several time‐points. Further core genome phylogenetic analysis using ClonalFrame revealed a formation of a distinct monophyletic lineage by these two CCs, suggesting a certain degree of clonality of the C. jejuni population adapted to barnacle geese. Therefore, although STs also commonly found in humans patients (e.g. ST‐45) were among the barnacle geese C. jejuni isolates, this reservoir is probably an infrequent source for human campylobacteriosis.  相似文献   

6.
To explore the clinical significance of campylobacter infections for dogs and cats we compared intestinal carriage rates for Campylobacter sp. between animals with gastroenteritis and healthy controls. We cultured fecal specimens of 405 diarrheic dogs and 203 cats as well as 71 asymptomatic dogs and 35 cats using a selective medium in addition to filtration on a non-selective blood agar plate. We identified 224 campylobacter isolates using conventional phenotypic tests and DNA hybridization. There were 112 isolates, of C. upsaliensis, 43 C. jejuni and 69 other Campylobacter sp. For cats, there was no association between campylobacter carriage and disease, irrespective of the animals age. For dogs older than 12 months there was also no difference in campylobacter carriage rates between diarrheic and healthy animals. However, in younger dogs 44% of animals with diarrhea shed campylobacters in their feces, more than twice the rate in asymptomatic controls (21%), a significant difference. C. jejuni and C. upsaliensis contributed equally to this association between diarrhea and campylobacter prevalence. The parallel use of two culture methods enabled us to show that the recovery of Campylobacter sp. by filtration may be less than optimal and that filtering is probably unsuitable as a reference method for culturing C. upsaliensis. Finally we found that almost half of the campylobacter isolates from cats belong to a phenotypically homogeneous group of strains closely resembling C. upsaliensis but hybridizing only weakly with C. upsaliensis DNA.  相似文献   

7.
A 1-year cross-sectional study was carried out to determine the prevalence, risk factors for carriage, and genetic diversity of Campylobacter spp. in healthy dogs and cats in Switzerland. Veterinary practitioners collected samples from 1268 animals (all ages) presented for vaccination. The prevalence of Campylobacter spp. in 634 dogs and 596 cats that were eligible for the study was 41.2% (confidence interval 95%: 37.3-45.1%) and 41.9% (CI 95%: 37.9-46%), respectively. Risk factors identified for carriage of Campylobacter jejuni were found to be different from risk factors for C. upsaliensis/C. helveticus. Young animals (< or =3 years) had significantly higher odds of carrying C. upsaliensis/C. helveticus than older animals (OR 1.8-3.3), whereas for C. jejuni carriage, the age was not a risk factor. Amplified fragment length polymorphism (AFLP) genotyping revealed heterogeneity among C. jejuni strains and was found to clearly separate C. helveticus from C. upsaliensis. It was shown that cats more often carry C. helveticus with an estimated prevalence of 28.2%, whereas dogs mainly are carrying C. upsaliensis.  相似文献   

8.
Dog ownership is considered a risk factor for campylobacteriosis in humans. This study investigated the prevalence and shedding of Campylobacter spp. in kennelled dogs. Faecal samples (n=399) were collected in longitudinal studies from 52 dogs in two kennels. Campylobacter spp. were isolated using charcoal-based selective agars and direct PCR. The prevalence of Campylobacter spp. in dogs in boarding kennels ranged from 46% (95% CI 22, 72) on entry, to 50% (95% CI 30, 70) overall, and in dogs in 'rescue' kennels from 68% (95% CI 49, 84) on entry to 73% (95%, CI 56, 87) overall. C. upsaliensis was isolated from 62% (95% CI 48, 73) of the dogs, whilst C. jejuni was isolated from 15% (95% CI 7, 26) of animals. The majority of infected dogs entered the kennels already carrying Campylobacter spp., and remained infected throughout their stay. However, in some cases, shedding appeared to commence after kennelling. Given that the prevalence of C. upsaliensis and C. jejuni was relatively high in dogs from both boarding and rescue kennels, such animals may pose a zoonotic risk.  相似文献   

9.
Abstract

AIMS: To investigate the prevalence of Campylobacter spp. and C. jejuni in dog faecal material collected from dog walkways in the city of Palmerston North, New Zealand, and to characterise the C. jejuni isolates by multilocus sequence typing (MLST) and porA and flaA antigen gene typing.

METHODS: A total of 355 fresh samples of dogs faeces were collected from bins provided for the disposal of dog faeces in 10 walkways in Palmerston North, New Zealand, between August 2008–July 2009. Presumptive Campylobacter colonies, cultured on modified charcoal cefoperazone deoxycholate plates, were screened for genus Campylobacter and C. jejuni by PCR. The C. jejuni isolates were subsequently characterised by MLST and porA and flaA typing, and C. jejuni sequence types (ST) were assigned.

RESULTS: Of the 355 samples collected, 72 (20 (95% CI=16–25)%) were positive for Campylobacter spp. and 22 (6 (95% CI=4–9)%) were positive for C. jejuni. Of the 22 C. jejuni isolates, 19 were fully typed by MLST. Ten isolates were assigned to the clonal complex ST-45 and three to ST-52. The allelic combinations of ST-45/flaA 21/porA 44 (n=3), ST-45/flaA 22/porA 53 (n=3) and ST-52/ flaA 57/porA 905 (n=3) were most frequent.

CONCLUSIONS: The successful isolation of C. jejuni from canine faecal samples collected from faecal bins provides evidence that Campylobacter spp. may survive outside the host for at least several hours despite requiring fastidious growth conditions in culture. The results show that dogs carry C. jejuni genotypes (ST-45, ST-50, ST-52 and ST-696) that have been reported in human clinical cases.

CLINICAL RELEVANCE: Although these results do not provide any evidence either for the direction of infection or for dogs being a potential risk factor for human campylobacteriosis, dog owners are advised to practice good hygiene with respect to their pets to reduce potential exposure to infection.  相似文献   

10.
Streptococci are one among the major mastitis pathogens which have a considerable impact on cow health, milk quality, and productivity. The aim of the present study was to investigate the occurrence and virulence characteristics of streptococci from bovine milk and to assess the molecular epidemiology and population structure of the Indian isolates using multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Out of a total of 209 bovine composite milk samples screened from four herds (A–D), 30 Streptococcus spp. were isolated from 29 milk samples. Among the 30 isolates, species-specific PCR and partial 16S rRNA gene sequence analysis identified 17 Streptococcus agalactiae arising from herd A and 13 Streptococcus uberis comprising of 5, 7, and 1 isolates from herds B, C, and D respectively. PCR based screening for virulence genes revealed the presence of the cfb and the pavA genes in 17 and 1 S. agalactiae isolates, respectively. Similarly, in S. uberis isolates, cfu gene was present in six isolates from herd C, the pau A/skc gene in all the isolates from herds B, C, and D, whereas the sua gene was present in four isolates from herd B and the only isolate from herd D. On MLST analysis, all the S. agalactiae isolates were found to be of a novel sequence type (ST), ST-483, reported for the first time and is a single locus variant of the predicted subgroup founder ST-310, while the S. uberis isolates were found to be of three novel sequence types, namely ST-439, ST-474, and ST-475, all reported for the first time. ST-474 was a double locus variant of three different STs of global clonal complex ST-143 considered to be associated with clinical and subclinical mastitis, but ST-439 and ST-475 were singletons. Unique sequence types identified for both S. agalactiae and S. uberis were found to be herd specific. On PFGE analysis, identical or closely related restriction patterns for S. agalactiae ST-483 and S. uberis ST-439 in herds A and B respectively, but an unrelated restriction pattern for S. uberis ST-474 and ST-475 isolates from herds D and C respectively, were obtained. This signifies that the isolates of particular ST may exhibit related PFGE patterns suggesting detection of a faster molecular clock by PFGE than MLST. Since all the isolates of both the species belonged to novel sequence types, their epidemiological significance in global context could not be ascertained, however, evidence suggests that they have uniquely evolved in Indian conditions. Further research would be useful for understanding the role of these pathogens in bovine sub-clinical mastitis and implementing effective control strategies in India.  相似文献   

11.
Using a newly formulated selective medium containing cefoperazone, we isolated 72 Campylobacter strains in fecal samples from 397 diarrheic dogs and cats. Of these, 39 were thermophilic catalase-negative Campylobacter species. We identified these Campylobacter strains by DNA:DNA hybridization, using digoxigenin-labeled total genomic DNA of 4 Campylobacter reference strains (C jejuni, C coli, C lari, and C upsaliensis) as a probe. The labeling was done with a commercially available kit. We could identify 66 of the 72 Campylobacter isolates to the species level with this method; identification with probes always agreed with conventional test results. Of the 66 identified strains, 33 were C upsaliensis and 33 were C jejuni. Six isolates could not be assigned to a known species with probes or conventional tests. On the basis of our findings, C upsaliensis is more resistant to cefoperazone than to cephalothin, thereby explaining the unexpected recovery of these campylobacters on cephalosporin-containing media.  相似文献   

12.
BACKGROUND: Campylobacter enteritis was the most frequently notified infectious disease in Australia in 1996 and Campylobacter species have been associated with extra-intestinal infections such as purulent arthritis and Guillian-Barré syndrome. Dogs and cats are known to carry campylobacteria and contact with household pets have been implicated as possible sources of human infection. OBJECTIVE: To provide information on the species of campylobacter carried by cats and dogs in South Australia. METHODS: Faecal samples were collected from stray and owned cats and dogs and feral cats. Campylobacter-like organisms were isolated using selective media and filtration methods. They were then characterised by biochemical tests, antibiotic resistance and growth patterns under various conditions. Husbandry factors that could have influenced the carriage rates were examined both as single variables and in a multivariate logistic regression. RESULTS: Campylobacter upsaliensis and C jejuni were found in 11% and 4% of cats, respectively, whereas 34% dogs carried C upsaliensis, 7% C jejuni and 2% C coli. Intensive housing and open drains were found to be significant risk factors and increased the carriage rate by 2 and 2.6 times, respectively. CONCLUSION: Dogs and cats are a potential reservoir for human enteric infections with campylobacters.  相似文献   

13.
Cryptosporidium parvum is a zoonotic pathogen composed of genetically distinct but morphologically identical genotypes. Recent molecular study indicates that dogs may transmit the cattle genotype, which is known to be pathogenic to humans. Although large-scale studies of Cryptosporidium infection in dogs have been performed in several countries, the isolates were not accurately identified because of the lack of a method for molecular analysis. It is important to identify the isolates harbored in dogs, which come in close contact with humans, in order to control human cryptosporidiosis. The aim of the present study was to calculate the prevalence of Cryptosporidium infection in dogs in Osaka city, Japan, and to characterize the isolates molecularly. The prevalence was determined to be 9.3% (13/140) by PCR. All isolates were found to be Cryptosporidium canis (previously known as the dog genotype), which is thought to be non-pathogenic in humans, based on the sequencing of diagnostic fragments. These results indicate that PCR-based diagnostic methods are a useful tool for the diagnosis and molecular epidemiology of Cryptosporidium infection in dogs, and that dogs living in Osaka are not a significant reservoir for human cryptosporidiosis. It is unclear why C. canis is dominant in dogs. Further study is required to understand this partial parasitism.  相似文献   

14.
BACKGROUND: Anaplasma phagocytophilum (formerly known as the human granulocytic ehrlichia, Ehrlichia equi and Ehrlichia phagocytophila) is an obligate intracellular organism causing clinical disease in humans and various species of domestic animals. OBJECTIVES: The objectives of this investigation were to sequence and clone the major surface protein 5 (MSP5) of A phagocytophilum and to evaluate the suitability of this antigen in the serologic diagnosis of anaplasmosis in humans and dogs. METHODS: The msp5 gene of A phagocytophilum was sequenced, cloned, and expressed in Escherichia coli. The predicted amino acid sequence homology of the various MSP5/major antigenic protein 2 orthologs was compared among various Anaplasma and Ehrlichia species. Recombinant MSP5 of A phagocytophilum was used in an ELISA to detect antibodies in serum samples from humans and dogs infected with the organism. RESULTS: Serum samples from 104 individuals previously diagnosed with A phagocytophilum infection, as well as samples from clinically healthy humans, were tested. In addition, multiple samples from 4 dogs experimentally infected with 2 different geographic isolates of A phagocytophilum and 5 dogs naturally infected with a Swiss isolate were tested using ELISA. Using this group of immunofluorescent antibody test-positive and immunofluorescent antibody test-negative samples, we found the overall agreement between assays to be >90%. CONCLUSIONS: These results indicate that recombinant MSP5 has potential for use as a diagnostic test antigen to detect infection with A phagocytophilum in both dogs and humans. However, sequence similarities among orthologs of MSP5 in related species of anaplasma and ehrlichia suggest that cross-reactivity among these pathogens is likely if the entire peptide is used as a test antigen.  相似文献   

15.
To study the diversity of Cryptosporidium spp. in various hosts, we used the variability of the small-subunit rRNA gene and the Cryptosporidium oocyst wall protein genes. Oocysts from humans, cattle, horses, dogs, field mice, chickens, reptiles, deer, goat, cat, antelope and from a sample of water reservoir were assayed. The zoonotic C. parvum bovine genotype sequence was found to be present in the most of isolates. This study shows a complex epidemiology pattern for C. parvum bovine genotype infections. The identification of cattle, horse, and deer isolates emphasizes a transmission route for C. parvum via these hosts, and identifies a potential source for human infection in the Czech Republic. Furthermore, C. andersoni from a cow, C. baileyi from a chicken, C. felis from a cat, C. meleagridis from a dog, and C. saurophilum and C. serpentis from reptiles were also identified in the isolates from the Czech Republic.  相似文献   

16.
The emergence of NDM‐producing Escherichia coli has considerably threatened human and animal health worldwide. This study describes for the first time in Egypt, the draft genome sequences of emerging NDM‐5‐producing E. coli from humans and dogs, and investigates genetic relatedness between isolates from both sources. Two E. coli from human urine and seven from environmental clinical samples of dogs exhibited resistance to carbapenems and harbouring blaNDM were subjected to Illumina Miseq whole‐genome sequencing (WGS). Assembly and analysis of the reads were performed to identify resistance genes, multilocus sequence types (MLST), plasmid replicon types (Inc) and insertion sequences (IS) of the blaNDM region; core genome MLST (cgMLST) analysis was also performed. Two different NDM alleles were identified; blaNDM‐5 in E. coli HR119 from the urine of a healthy person and environmental samples of dogs, and blaNDM‐1 in E. coli HR135 from a human patient's urine. Multiple mobilizable resistance genes to different antimicrobial classes were identified except the colistin resistance gene, mcr. E. coli isolates from humans and dogs were assigned to different sequence types (STs). Using cgMLST, dog isolates clustered together with only 1–2 allellic differences; however, human E. coli showed 1,978 different allelles compared with dog isolates. Plasmidfinder results indicated the presence of an IncX3 replicon in blaNDM‐5‐producing E. coli; however, blaNDM‐1 was linked to IncCoIKP3. Notably, the NDM region (3 Kb) in all isolates from humans and dogs was highly similar with variable flanking sequences that represented different IS elements. This study reports the first emergence of NDM‐5‐producing E. coli from dogs in Egypt that shared some genetic features with human isolates and could be considered potential public health threats.  相似文献   

17.
Clostridium difficile-associated-diarrhea (CDAD) is a nosocomial infection in dogs. Diagnosis of this infection is dependent on clinical signs of disease supported by laboratory detection of C. difficile toxins A or B, or both, in fecal specimens via enzyme-linked immunosorbent assay (ELISA). Unfortunately, to the authors' knowledge, commercially available ELISAs have not been validated in dogs to date. We evaluated 5 ELISAs done on 143 canine fecal specimens (100 diarrheic and 43 nondiarrheic dogs) and on 29 C. difficile isolates. The results of each ELISA were compared with the cytotoxin B tissue culture assay (CTA). Clostridium difficile was isolated from 23% of the fecal specimens. Eighteen of the 143 fecal specimens were toxin positive (15 diarrheic and 3 nondiarrheic dogs). On the basis of multiplex polymerase chain reaction (PCR) analysis for toxin-A and -B genes, 72% of the isolates were toxigenic. The carriage rate of toxigenic isolates in diarrheic dogs was higher than that in the nondiarrheic dogs; however, these differences were not statistically significant. A good correlation was found between CTA, PCR, and culture results. The ELISAs done on fecal specimens collected from diarrheic dogs had low sensitivity (7-33%). In contrast, ELISA for toxin A or B, or both, performed on toxigenic isolates had high sensitivity (93%). These results suggest that commercially available human ELISAs are inadequate for the diagnosis of canine C. difficile-associated diarrhea when tested on fecal specimens. In contrast, the Premier ToxinA/B and Techlab ToxinA/B ELISAs may be useful for the diagnosis of canine CDAD when used on toxigenic isolates.  相似文献   

18.
Blastocystis is a common intestinal parasite among humans and animals such as non-human primates, pigs, cattle, birds, amphibians, and less frequently, rats, reptiles and insects. Since Blastocystis is a widely transmissible parasite between humans and mammals or birds, it is prominent to determine whether newly secluded non-human isolates are zoonotic. There are no comprehensive studies in Iran assessing the prevalence and molecular identification of Blastocystis infection in birds, especially in pigeons and crows. So, the aim of this study was to identify Blastocystis subtypes (STs) in crows and pigeons in Tehran province, Iran, using Nested PCR-RFLP and sequencing. Overall, 300 Blastocystis isolates from birds (156 pigeons and 144 crows) were subtyped by PCR, and the homology among isolates was then confirmed by RFLP analysis of the 18S rRNA gene. The prevalence of Blastocystis infection was detected 42.9% in pigeons and 44.4% in crows. All positive pigeons were owned by ST13 (100%). Among crows, 46 samples (71.8%) like pigeons were ST13, and 13 samples (20.3%) were ST14. Five samples (7.9%) remained unknown. This study was the first report of ST13 and ST14 of Blastocystis from birds. In the present study, our data revealed a high prevalence of Blastocystis sp. in pigeon’s and crow’s samples and the isolates from these birds were classified into two genetically distinct STs. Therefore, birds appear to be infected with various STs. It is important to determine the phylogenetic relationships between unknown STs from these birds and the multiple STs of Blastocystis.  相似文献   

19.
In humans, the glycosylation pattern of serum and of membrane glycoproteins is associated with invasiveness of tumors: specifically, α2,6-sialylation and α2,3-sialylation are associated with metastasizing and nonmetastasizing tumors, respectively. In turn, the type of sialylation depends on the activity of α2,6 or α2,3 sialyltransferase (ST) enzymes. Because of the high prevalence of metastasizing tumors with biological behavior similar to the human counterpart, female dogs with metastasizing neoplasms could provide a good animal model for investigating the potential roles of sialic acid (Sia) and ST enzymes in the pathogenesis of metastatic tumors. The aims of this study were (1) to validate a solid-phase method based on lectin staining of serum and tissue homogenates to investigate sialylation and ST activity and (2) to compare the results obtained with this method and with lectin staining and to collect preliminary information on sialylation and ST activity in dogs with (n = 8) and without (n = 8) mammary tumors. The data recorded in healthy dogs revealed that serum and tissue glycoproteins are prevalently characterized by a α2,6 sialylation, but ST-α2,3 seems to be the most active enzyme in both samples. Sia-α2,3 and ST-α2,3 activity decreases in serum and tissues of dogs with tumors, especially in a dog with metastasis, suggesting that the equilibrium between ST-α2,6 and ST-α2,3 activity shifts toward the former, as reported in humans.  相似文献   

20.
OBJECTIVE: To assess the prevalence and patterns of antimicrobial resistance among Escherichia coli strains isolated from the urine of women with cystitis or pyelonephritis and from fecal samples from dogs and healthy humans. DESIGN: Cross-sectional survey. SAMPLE POPULATION: Escherichia coli isolates from 82 women with cystitis, 170 women with pyelonephritis, 45 dogs, and 76 healthy human volunteers. PROCEDURE: Susceptibility to 12 antimicrobial agents was determined by means of disk diffusion testing as specified by the NCCLS. RESULTS: Overall, the 4 most common antimicrobial resistance patterns were resistance to ampicillin, sulfisoxazole, trimethoprim, and trimethoprim-sulfamethoxazole (n = 45 [12% of all isolates]); ampicillin alone (33 [9%]); ampicillin and sulfisoxazole (29 [8%]); and sulfisoxazole alone (14 [4%]). None of the isolates were resistant to ceftazidime, ciprofloxacin, nitrofurantoin, or piperacillin-tazobactam. Resistance was significantly more common and extensive among isolates from women with cystitis or pyelonephritis than among isolates from healthy humans or dogs. Resistance was least common among isolates from dogs. The only resistance phenotype that was more common among canine isolates than human isolates was resistance to sulfisoxazole alone. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that dogs are unlikely to be an important external reservoir of antimicrobial-resistant E. coli strains causing infections in humans. On the contrary the data suggest that dogs conceivably could acquire resistant E. coli strains from humans.  相似文献   

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